Category effects in temporal visual search.

When subjects identify a target during rapid serial visual presentation (RSVP), they show a reduced ability to detect a subsequent probe stimulus relative to when they ignore the target. The present study demonstrated an effect of target/probe categorical relation upon this probe detection deficit (attentional blink). Experiment 1 used letters for both target and probe, replicating the general methods and results of Raymond, Shapiro, and Arnell (1992). Experiment 2 varied target/probe categorical relation via instructional set: The target was referred to as the letter 'oh', whereas for other subjects it was referred to as the number 'zero.' Treating O as a number attenuated the probe detection deficit. This different-category attenuation was confirmed in Experiment 3 where the target was a letter and the probe was a number. The observed category effect suggests that the probe detection deficit in RSVP may map a time course from spreading intra-category inhibition following temporal target selection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Erosion of copper single crystals under conditions of 90° impact

High purity copper single crystals were eroded parallel to [111] at 90° to the surface with glass spheres 70 μm in diameter travelling at a velocity of 122 m s^?1. Detailed scanning electron microscopy of eroded surfaces together with transmission electron microscopy of both erosion debris and near-surface layers of the target was performed. It was observed that a hilland-valley surface topology developed ; this has not been reported previously and gave rise to a local low angle cutting component of erosion at 90°. Direct evidence was obtained of a transient heating effect from the particle impact as well as the formation of subsurface voids in heavily deformed regions. In addition it was shown that subsurface cracking produced a flaking mechanism of material loss.     

An Efficient Procedure for Implementing a Dual Simplex Network Flow Algorithm

This paper shows that for linear programming formulations of network flow problems, the nonzero components of rows of the basis inverse are identical. A simple algorithm for identifying these nonzero components is given along with a suggested data structure for implementation. The algorithm requires only one bit of storage for each node plus one additional bit. Finally we indicate how these ideas may be used in the development of a dual simplex code for network flow problems.     

Diet, alcohol, and physical activity as a function of smoking status in middle-aged women.

Diet, alcohol intake, and leisure-time physical activity were compared cross-sectionally in middle-aged female smokers, ex-smokers, and never smokers and were reassessed approximately 3 yrs later. At initial contact, there were no group differences in total caloric intake and very few differences in nutrient intake, but alcohol intake of current smokers and ex-smokers was at least 50% greater than that of never smokers, and current smokers reported less physical activity than did ex-smokers and never smokers. Prospective findings were similar: Compared with continuing smokers, ex-smokers did not change their dietary and alcohol intake but significantly increased physical activity. Thus, some adverse behaviors associated with smoking (e.g., alcohol intake) may be due to self-selection to history of smoking, whereas other behaviors (e.g., reduced physical activity) may be directly related to smoking itself. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A comparative survey of therapist sexual misconduct between an American state and an Australian state.

In this study, the authors surveyed all licensed psychologists in the state of Rhode Island and in the state of Western Australia, Australia, and asked them if they had treated clients who had been sexually abused by a former therapist. Surveys distributed in both states were nearly identical, with only minor differences to conform to local conventions. Despite some very distinct cultural and training differences between the two professional psychology populations, there was remarkable similarity in the percentage of respondents who reported having treated victims of therapist sexual abuse. Both populations of psychologists also judged the effects of such sexual relations to be detrimental to patients, though U.S. psychologists were much more aware of therapist sexual abuse issues than Australian psychologists. This study is the first to provide survey data on this phenomenon in Australia and the first cross-cultural comparison. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A method of smoothing digital thematic maps

A method has been developed for the smoothing of digital thematic maps such as those derived from LANDSAT data. The method permits one to specify a minimal area for each feature represented on the map. After application of the method all the regions belonging to any given feature have areas equal to or greater than the minimum for the feature. In this report the results are presented for a particular example.     

Spatial-time dynamics of the discharge pumping and lasing in a XeClexcimer laser

Spatial-time density distributions of excited components (Xe*, He*, Xe⁺*, XeCl*, free electrons) and the lasing intensity were measured by the pulse-dye-laser absorption (gain) probing of the active medium of a XeCl discharge laser. Some general regularities of the local deposition rate dynamics and active medium formation processes have been obtained. The influence of the electric field and preionization nonuniformities on the discharge profile is discussed. It is shown that the spatial profile, for the number of plasmochemical reactions leading to the formation of this component. The effect of the discharge layering is explained on the basis of the density gradients of excited on the basis of the density gradients if excited components and the oscillating pumping     

Mariposa: a wide-area distributed database system

The requirements of wide-area distributed database systems differ dramatically from those of local-area network systems. In a wide-area network (WAN) configuration, individual sites usually report to different system administrators, have different access and charging algorithms, install site-specific data type extensions, and have different constraints on servicing remote requests. Typical of the last point are production transaction environments, which are fully engaged during normal business hours, and cannot take on additional load. Finally, there may be many sites participating in a WAN distributed DBMS. In this world, a single program performing global query optimization using a cost-based optimizer will not work well. Cost-based optimization does not respond well to site-specific type extension, access constraints, charging algorithms, and time-of-day constraints. Furthermore, traditional cost-based distributed optimizers do not scale well to a large number of possible processing sites. Since traditional distributed DBMSs have all used cost-based optimizers, they are not appropriate in a WAN environment, and a new architecture is required. We have proposed and implemented an economic paradigm as the solution to these issues in a new distributed DBMS called Mariposa. In this paper, we present the architecture and implementation of Mariposa and discuss early feedback on its operating characteristics. Edited by Henry F. Korth and Amith Sheth. Received November 1994 / Revised June 1995 / Accepted September 14, 1995     

Depression, self-focused attention, and the negative memory bias.

On the basis of self-regulatory perseveration theory, we hypothesized that the negative memory bias commonly found among depressed people is mediated by excess levels of self-focused attention and thus can be reduced by preventing depressed people from focusing on themselves. In Experiment 1, nondepressed and subclinically depressed college students were induced to either focus on themselves or externally and then to recall 10 events that had happened to themselves during the previous 2 weeks. Consistent with our hypotheses, events recalled by depressed Ss were more negative than events recalled by nondepressed Ss under conditions of self-focus but not under conditions of external focus. We conducted Experiment 2 to determine whether this effect was specific to self-referent events or generalizable to events that happened to other people. Experiment 2's findings replicated the previous findings for self-referent events but showed a different pattern for recall of events that happened to others, suggesting that self-focus reduces the negative memory bias among depressed individuals by deactivating their self-schemas. Theoretical and practical implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)